Impossible For CO2 to Heat Oceans
in [Physics]
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From: Lloyd Parker on 6 Sep 2006 07:08 In article <RWuLg.24200$rP1.5307(a)news-server.bigpond.net.au>, Orator <Orator(a)troll.bridge.net> wrote: >Phil. wrote: > >> Orator wrote: >> >>>Phil. wrote: >>> >>> >>>>Retief wrote: >>>> >>>> >>>>>On 1 Sep 2006 19:06:15 -0700, "Phil." <felton(a)princeton.edu> wrote: >>>>> >>>>> >>>>> >>>>>>Orator wrote: >>>>>> >>>>>> >>>>>>>Fact is if any radiation is blocked at all (no allowed to escape), it >>>>>>>will eventually result in that effect as they claim a cumulative effect. >>>>>>>It is not "strawman", it is the inevitable consequence of the claim made. >>>>>>> >>>>>>>Why that is so is that the effect on incoming radiation is never >>>>>>>considered by the GW religion - it brings things back to a balance, when >>>>>>>it IS considered. >>>>>> >>>>>>Except as you've been told many times before it is considered, incoming >>>>>>IR is not blocked it is absorbed. >>>>> >>>>>Orator did not make the claim that IR was _blocked_, but rather that >>>>>claim was from the AGW supporter and Usenet troll "WFHCS" did. Orator >>>>>simply explained the consequences of _blocking_ this radiation. >>>>> >>>>>BTW, you forgot to mention that absorbed IR energy is subsequently >>>>>re-emitted -- otherwise you have effectively claimed "it is blocked". >>>>>As I explained previously, it's an energy balance - and not "blocked". >>>>> >>>> >>>> >>>>And I wish I had a buck for every time I've explained that to Orator, >>>>his claim that incoming IR wasn't considered has been refuted many >>>>times, in detail, he just prefers to continue lying about it! >>> >>>I remind you of what Retief stated "you forgot to mention that absorbed >>>IR energy is subsequently re-emitted". So using the term "absorbed" or >>>"blocked" makes no difference as the effect is the same. Without that >>>re-emission, the heat becomes cumulative. >> >> As I pointed out to Retief it's much more likely to lose that energy by >> collision in the lower troposphere. > >Really :-) > >Lets make this clear. You say a CO2 molecule blocks/absorb heat (to use >short hand). Then it hangs on to this heat till it travels down the >atmosphere against all laws of physics, until bad driving caused it to >have an accident and it collides, releasing the heat. > Most molecules do release their energy in collisions. >Of course this interesting chain of events needs a full explanation from >you regarding these points. > >Please establish with proof, be it evidence, citation to a reputable >study or sound logic, that radiation is actually blocked/absorbed, in >other words retained by the molecule. It requires the mechanism for it >to hold that radiation and prevent it leaking out. Bond vibrations. That's how molecules absorb IR in the first place. >
From: Robert Grumbine on 6 Sep 2006 14:53 In article <CNqdnYgsx9diJGnZnZ2dnUVZ_r6dnZ2d(a)giganews.com>, Bob Cain <arcane(a)arcanemethods.com> wrote: >Hoggle wrote: >> kdthrge(a)yahoo.com wrote: >>> Evidence of dark spectroscopic bands is not >>> evidence of heat retention. >> >> And here we get to the heart of your ignorance with respect to >> greenhouse warming. There is no part of the global warming theory that >> requires CO2 to warm up as a result of IR absorbtion. The only >> requirement is that the radiation be absorbed and then re-emitted in a >> random direction. By so doing, it interrupts the outwards path and >> allows 50% of the radiation to return earthwards and thus remain part >> of the overall system. Reducing the escape of energy from the system is >> the only thing necessary for global warming to be a reality. > >At last the heart of the matter. Now, can someone explain, for the >sake of those like myself who don't know about this stuff, exactly >what it is about CO2 that gives it special IR absorption properties in >the wavelengths involved in the earth's re-emission spectrum? > >What are those properties? Are there graphs that can be downloaded >that depict these absorption properties for various atmospheric gases >as a function of wavelength normalized to the earth's re-emission >spectrum? The HITRAN data base and programs will give you the most detailed answers as to the observed behaviors. Most molecules with more than 2 atoms involved act as greenhouse gases. There's nothing special about CO2 in this regard. The reason is that polyatomics have modes in which they can transfer energy between vibration and rotation, with energy levels which correspond to the infrared. Monatomics can only absorb/emit at energy levels of electron transitions (visible and UV for the most part) and diatomics' don't permit the rotation-vibrational transitions. For more detail on exactly why these are the quantum mechanics of molecules, see Herzberg's classics. By Kirchoff's law, anything which absorbs at a frequency, emits at it as well (equally well), hence my absorb/emit above. >How can the gas in the trace quantities at which it is present have >such a large impact on atmospheric temperature? All radiatively important gases are in trace quantities if you integrate over the full atmosphere. This includes the popular water vapor, whose concentration is only 'high' near the surface of the earth. This gives us surface dwellers a biased view of things. How they manage to be important is that the earth radiates at wavelengths that these gases absorb. Once absorbed, they re-emit half downward (leading to warming of the surface) and let the other half go on to space (as it was in the first place). Within their frequencies of absorption, gases are very effective at absorbing energy. i.o.w., trace concentrations are enough to absorb the surface emission. >How can the low total heat capacity of the atmosphere relative to that >of the oceans result in significant temperature increase of the >oceans? In analogy with electrical capacitance, what is the ratio of >that of the oceans to that of the atmosphere? Wrong analogy. The heating of the ocean for the radiative case doesn't work by first heating up the atmosphere and then communicating that warming to the ocean by contact. What happens instead is that the greenhouse gases add a long wave (same bands as the earth's radiation) component downwards to the ocean. (In addition to the solar (shortwave) and latent and sensible heat fluxes). The radiative change from doubled CO2 (a reference sort of figure) is about 4 W/m^2. Given that the heat capacity of the ocean is enormous, this leads to only slow changes in ocean temperature. For reference, specific heat of sea water is about 4000 J/kg/K and density is about 1000 kg/m^3. A ballpark wind-mixed layer depth is 100 m, while the thickness above the permanent thermocline is about 1000 m. Figure up how long it would take to get a 1 K warming with 4 W/m^2. -- Robert Grumbine http://www.radix.net/~bobg/ Science faqs and amateur activities notes and links. Sagredo (Galileo Galilei) "You present these recondite matters with too much evidence and ease; this great facility makes them less appreciated than they would be had they been presented in a more abstruse manner." Two New Sciences
From: Bob Cain on 6 Sep 2006 16:18 mmeron(a)cars3.uchicago.edu wrote: > The extra kinetic energy a molecule acquires following the absorption > of a visible (or less) photon is quite negligible. The energy is > absorbed into vibrational or rotational degrees of freedom. Oh. Thanks. How is that energy shared with the molecule's neighbors? Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein
From: Bob Cain on 6 Sep 2006 16:50 Many thanks for explaining these things. Some questions remain if you don't mind. Robert Grumbine wrote: > By Kirchoff's law, anything which absorbs at a frequency, emits > at it as well (equally well), hence my absorb/emit above. So the energy absorbed is re-emitted in random directions rather than being shared with neighbors by kinetic processes. Right? At what point, then, is this captured energy converted to the kinetic form that determines atmospheric temperature? > What happens instead is that the greenhouse gases add a long wave > (same bands as the earth's radiation) component downwards to the ocean. > (In addition to the solar (shortwave) and latent and sensible heat > fluxes). The radiative change from doubled CO2 (a reference sort of > figure) is about 4 W/m^2. Given that the heat capacity of the ocean > is enormous, this leads to only slow changes in ocean temperature. For > reference, specific heat of sea water is about 4000 J/kg/K and density > is about 1000 kg/m^3. A ballpark wind-mixed layer depth is 100 m, while > the thickness above the permanent thermocline is about 1000 m. Figure > up how long it would take to get a 1 K warming with 4 W/m^2. With a 40 year old EE degree I'm too far removed from even that basic stuff to take any calculation on. :-) You seem to imply that it's a long time. Yet it is fast enough to account for the ocean warming has been observed and predicted? If the ocean temperature remains fairly constant over short time periods is the atmosphere that is above the oceans subject to the same radiative forcing as that over land? I'm still having trouble understanding how this redirected long wave radiation will increase air conditioning costs. :-) Thanks Again, Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein
From: mmeron on 6 Sep 2006 17:31
In article <7qCdnUcL05SEsGLZnZ2dnUVZ_sadnZ2d(a)giganews.com>, Bob Cain <arcane(a)arcanemethods.com> writes: >mmeron(a)cars3.uchicago.edu wrote: > >> The extra kinetic energy a molecule acquires following the absorption >> of a visible (or less) photon is quite negligible. The energy is >> absorbed into vibrational or rotational degrees of freedom. > >Oh. Thanks. > >How is that energy shared with the molecule's neighbors? > It can be transferred during collisions, or emitted as a photon. Mati Meron | "When you argue with a fool, meron(a)cars.uchicago.edu | chances are he is doing just the same" |